ceph/src/boost/libs/fusion/include/boost/fusion/iterator/equal_to.hpp

   1 /*=============================================================================
   2     Copyright (c) 2001-2011 Joel de Guzman
   3
   4     Distributed under the Boost Software License, Version 1.0. (See accompanying
   5     file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   6 ==============================================================================*/
   7 #if !defined(FUSION_EQUAL_TO_05052005_1208)
   8 #define FUSION_EQUAL_TO_05052005_1208
   9
  10 #include <boost/fusion/support/config.hpp>
  11 #include <boost/type_traits/is_same.hpp>
  12 #include <boost/fusion/support/tag_of.hpp>
  13 #include <boost/type_traits/add_const.hpp>
  14 #include <boost/fusion/support/is_iterator.hpp>
  15 #include <boost/mpl/and.hpp>
  16 #include <boost/utility/enable_if.hpp>
  17
  18 namespace boost { namespace fusion
  19 {
  20     // Special tags:
  21     struct iterator_facade_tag; // iterator facade tag
  22     struct boost_array_iterator_tag; // boost::array iterator tag
  23     struct mpl_iterator_tag; // mpl sequence iterator tag
  24     struct std_pair_iterator_tag; // std::pair iterator tag
  25
  26     namespace extension
  27     {
  28         template <typename Tag>
  29         struct equal_to_impl
  30         {
  31             // default implementation
  32             template <typename I1, typename I2>
  33             struct apply
  34                 : is_same<typename add_const<I1>::type, typename add_const<I2>::type>
  35             {};
  36         };
  37
  38         template <>
  39         struct equal_to_impl<iterator_facade_tag>
  40         {
  41             template <typename It1, typename It2, typename Tag1, typename Tag2>
  42             struct dispatch : mpl::false_ {};
  43
  44             template <typename It1, typename It2, typename Tag>
  45             struct dispatch<It1, It2, Tag, Tag> // same tag
  46               : It1::template equal_to<It1, It2>
  47             {};
  48
  49             template<typename It1, typename It2>
  50             struct apply : dispatch<It1, It2,
  51                 typename It1::fusion_tag, typename It2::fusion_tag>
  52             {};
  53         };
  54
  55         template <>
  56         struct equal_to_impl<boost_array_iterator_tag>;
  57
  58         template <>
  59         struct equal_to_impl<mpl_iterator_tag>;
  60
  61         template <>
  62         struct equal_to_impl<std_pair_iterator_tag>;
  63     }
  64
  65     namespace result_of
  66     {
  67         template <typename I1, typename I2>
  68         struct equal_to
  69             : extension::equal_to_impl<typename detail::tag_of<I1>::type>::
  70                 template apply<I1, I2>
  71         {};
  72     }
  73
  74     namespace iterator_operators
  75     {
  76         template <typename Iter1, typename Iter2>
  77         BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
  78         inline typename
  79         boost::enable_if<
  80             mpl::and_<is_fusion_iterator<Iter1>, is_fusion_iterator<Iter2> >
  81             , bool
  82             >::type
  83         operator==(Iter1 const&, Iter2 const&)
  84         {
  85             return result_of::equal_to<Iter1, Iter2>::value;
  86         }
  87
  88         template <typename Iter1, typename Iter2>
  89         BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
  90         inline typename
  91         boost::enable_if<
  92             mpl::and_<is_fusion_iterator<Iter1>, is_fusion_iterator<Iter2> >
  93             , bool
  94             >::type
  95         operator!=(Iter1 const&, Iter2 const&)
  96         {
  97             return !result_of::equal_to<Iter1, Iter2>::value;
  98         }
  99     }
 100
 101     using iterator_operators::operator==;
 102     using iterator_operators::operator!=;
 103 }}
 104
 105 #endif
 106